Direct democracy is a political system where the citizens participate in the decision-making personally, contrary to relying on intermediaries or representatives. The use of a lot system, a characteristic of Athenian democracy, is unique to direct democracies.
As a general rule of thumb posts typically are 6-8 feet apart and are positioned on the corners, against the house and by the stairs of your deck. Mark the joists where the posts will go. Make sure they are even distance apart from one another. Next cut the posts to length.
The size of the boards used for beams depends on how far apart the posts are. 2x12 is typical for posts 10' apart with no other vertical support. If you have a stem wall and perimeter foundation, and you can put in additional studs to support the beam, 2x12 is unnecessary. 2x10 will be more than sufficient.